Cathead for drilling rigs



Nov. 11, 1941. I. 1-. MINYARD 2,262,694

CATHEAD FOR DRILLING RIG'S I Filed July 25, 1940 2 Sheets-Sheet 1 Irt IMlfiyard Patented Nov. 11, 1941 UNITED STATES PATE NT OFFICE 2 Claims.

. dependently of each other, in order to work two separate cat lines.

It is particularly aimed to provide such a structure as forms anattachment for drilling rigs, including a means attachable to the rotaryshaft of the latter and which accommodates the cathead normally attachedto such shaft.

The invention generally adds to the safety to operators since thewrapping of a rope around the conventional type of cathead and liftingarticles in the rig is extremely dangerous. The improvement renders itunnecessary to wrap the line around a spool since the steel line isfastened on one of the spools and upon being wound, lifts the load whichis attached to the other end of the line. There are of course variousother operations in oil well drilling which require the use of a catline and with the present invention, such jobs can be performed withgreater safety, speed and more economically.

Various additional objects and advantages will become apparent from aconsideration of the description following taken in connection withaccompanying drawings, illustrating an operative embodiment.

In said drawings:

Figure 1 is a side elevation of the construction;

Figure 2 is a vertical sectional view taken on the plane of line 2-2 ofFigure 1;

Figure 3 is a central longitudinal section taken on the plane of line3-3 of Figure 1;

Figure 4 is a cross section taken on the line 4-4 of Figure 3;

Figure 5 is a detail section illustrating one of the hydraulic devicesfor operating the yoke of the spinning line drum, and

Figure 6 is a detail section of one of the hydraulic devices foroperating the yoke of the derrick line drum.

Referring specifically to the drawings wherein like reference charactersdesignate like or similar parts, It) represents the rotary shaft of adrilling rig and H indicates a cathead of conventional construction andwhich is usually removably keyed to the shaft H]. In accordance with thepresent invention, a supplemental shaft is provided at I2 having one endportion l3 formed into a sleeve which receives and at I4 is keyed tothat end of shaft I0 on which the Auxiliary shaft I2 is held againstaxial displacement' by means of a rod I5 screwed at IE to a fixed nut orthe like I! fastened to the adjacent end of shaft ID. A disk l8 overlapsthe free end of auxiliary shaft l2, and a key l9 which engages thecathead H and rod l5 passes through disk l8 and beyond the same receivesa fastening nut or the like 20.

Loosely and slidably mounted on a portion 2| of auxiliary shaft l2, ofreduced diameter, is a spinning line spool or drum 22, the spinning lineof which is shown at 23. Roller bearings at 24 are operatively disposedbetween the drum 22 and shaft portion 2|. Drum 22 has a cone clutchflange or section 25, normally disengaged from butv engageable with acone clutch section or head 26 provided on the cathead H and which ispreferably lined as at 21.

The spinning line 23 is accommodated between the section 25 and a flange28 and between the latter and a flange 29, a shifting yoke 30 is mountedfor axial movement in either direction, the yoke having rollers 3|engageable with either flange 28 or 29. Such yoke 30 is preferably madein two sections having outwardly extending arms 32 bzolted together at33 as best shown in Figure On a portion 34 of auxiliary shaft I2, aderrick line drum or spool 35 is loosely and slidably mounted, withroller bearings 36 operatively disposed between the drum and saidenlarged portion. The derrick line is shown at 31 and accommodatedbetween a head or section 38 thereon and a flange 39. Section 38interiorly is conical and normally disengaged from but movable to engagea clutch head or section 39', of conical form, preferably lined as at40.

The periphery of section 38 constitutes a braking surface and it issurrounded by a contractile brake band 4|, normally disengagedtherewith. Movable in opposite directions between flange 39 and a flange4| on the drum 35, is a yoke 42 constructed similarly to the yoke 30 andhaving connected outwardly extending arms 43 similar to those at 32, theconnecting bolts or the like being indicated at 44. Yoke 42, has rollers45 mounted thereon for engagement with either flange 39 or 4|.

Hydraulic cylinders 46 and 47 are mounted in any suitable manner on theexterior of a generally cylindrical casing or housing 48 provided aboutthe operating parts and being adapted for attachment at one end 'to astationary part, of the drilling rig and for instance at a flange 43cathead ll of usual construction is carried. by means of bolts passedthrough openings 50,

Slidable in the cylinders 46 and 4! are pistons 48' and 49,respectively, having rods 50' and 5| extending through end walls thereofand con- I nected to the arms 32 and 43. Surrounding the rods 50' and5|, are coil springs 52 and 53, respectively, which maintain and urgethe pistons 48' and 49' to positions in which the associated yokes 30and 42 maintain the drums 22 and 35,

loose and unclutched. Such cylinders 46 and 41,

and pistons- 48' and'49 therein are under control of pressure lines frommaster cylinders, the pressure lines being shown connected as at 54 and55 to the respective cylinders. noted that the arms 32 and 43, extendthrough enlarged openings 56 and 51 of the casing 48.

It will be Reverting to the brake band 4|, it is anchored at one end asby means of a pin 58 to the casing 48 and its other end is fastenedas bymeans of a pin 59 to a manually operable lever 66 pivoted as at 6| tothe casing 48.

The spinning-line 23 passes out througha'suitable opening 62. in casing48,-its inner end being fastened to the drum 22.. The derrick 1iIiel3'1passes out from the casing throughan elongated fastened to the,

slot 63, and i its inner end is drum 35.

It'will be realized that up. the desired amount of line.

.Various changes. may be resorted they fall within vention.

I the arm win anow the shaft [0 and auxiliary shaft l2 to continue to;revolve after the drums 22 and 35 have spooled 7 so to provided thespirit and scope-of the inhydraulic cylinder and piston devices, andconnections from the yokes extending through the "casing and connectedto the piston devices.

2. A cathead construction of the class describedh'aving a rotatableshaft, a clutch head rigid thereon, a cathead rigid thereon having aclutch head, a spinning line drum loose and slidable on said shaft toengage and disengage one of said heads, a derrick line drum loose andslidable on said shaft to engage and disengagethe other of said heads, acasing surrounding said heads and drums, means operable to'slide thedrums mounted on the exterior of said casing, comprising yokes disposedabout-the drums, -.hydraulic cylinder and piston devices, connectionsfrom the yokes extending through the casing and connected to the pistondevices, and rollers on said yokes, said drums having flanges betweenwhich the rollers arejdisposed and which are engageable by' the rollers.

' IRA T. MINYARD.

